Expression profile of shikonin resistant K562 cell line

After over 25cycle and 18month's induction of shikonin, K562 cell show maginal resistance to shikonin but great change in gene expression We use microarray to detect the global gene expression change of shikonin resistant cell K562 cell was treated by 4uM shikonin for 4hours, then allowed to die and grow back in fresh medium. Once recovered, cells were immidiatly subjected to another treatment.